Three (Z) mono-unsaturated pheromones were synthesised by a method that used catalytic hydrogenation to bring about the reduction of two functional groups in one step. The procedure used inexpensive starting materials to produce the pheromones but, even though the reduction worked well, the introduction of an acid functionality increased the number of steps and the overall yields were reduced. Continuing the reductive methodology for the synthesis of aldehydes, a range of aldehyde pheromones were prepared including saturated, (Z)-mono-unsaturated and di-unsaturated. They were prepared from inexpensive starting materials and were generally produced, without the use of toxic oxidisers to give the aldehyde functionality. The key intermediates were the bromoaldehydes, which were produced through a range of chain lengths from six to eleven carbons. The aldehydes were protected as an acetal and the bromide coupled with a range of 1-alkynes to chain extend the molecule to the correct length before reducing the alkyne to a cis alkene. This gave the protected pheromone, which could be stored indefinitely and deprotected when ready, to give the aldehyde pheromone. Diene aldehyde pheromones were prepared using the same bromoaldehyde intermediate as a building block. E,Z-2,13-0ctadecadienal was synthesised using the same strategies as those used for the mono-unsaturated aldehydes. The Wittig coupling of bromononanal incorporated the conjugated aldehyde into the molecule.